Abstract: Through a process of creative engagement with the dominant culture, nineteenth-century American Catholic laywomen developed their own understanding of themselves and helped shape a distinctively Catholic gender system. This dissertation analyzes the beliefs and behaviors of Catholic laywomen as represented in four different source types: the letters of spinster-teacher Julia Compton, published obituaries, the popular novels of Mary Anne Sadlier and Anna Dorsey, and prescriptive literature. The sources reveal how the cultural systems of gender, religion, social class, ethnicity, and race interacted in complex and sometimes contradictory ways. For Catholic women writers in particular, the lived experience of their faith and concern about their marginalization both as women and as Catholics, led them to develop concepts of domesticity that privileged belief systems and behaviors over ethnicity and economic status. There were several avenues leading towards respectability and, in their imaginations, middle-class status. For them, the Catholic gender system was flexible and fluid, subsuming differences of marital status, ethnicity, and economic condition into domestic religious respectability. Catholic writers accepted and adapted some aspects of Protestant domesticity, such as the importance of education and charitable works, but challenged others, celebrating the use of Catholic devotional objects, and even granting a kind of agency to them. Outside of formal institutional channels, yet within the structure of their faith and the constraints of their society, Catholic laywomen practiced a kind of theology as they interpreted domestic ideology in ways that they perceived as empowering them as Catholics and as women.